<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<!-- opacity 0 - 1，用于改变透明度 -->
		<style type="text/css">
			*{
				margin: 0;
				padding: 0;
			}
			.wrap{
				width: 200px;
				height: 200px;
				background-color: pink;
				opacity: 0.5;
			}
		</style>
	</head>
	<body>
		<div class="wrap">
			
		</div>
	</body>
</html>
